Signaling apparatus



June 30, 1942. J. GANDL 2,288,084

SIGNALING APPARATUS Filed sept.- 2, 1938 2 sheets-sheet 1 ATTORNEYS,

June 30, 1942.. J. GANDL SIGNALING- APPARATUS Filed Sept.` 2, 1938 2 Sheets-Sheet 2 INVENTOR, ro/afanes G/za ATTORNEYS Patented June 39, 1942 nir seres 2,288,084 SIGNALING APPARATUS `lohannes Gandl, Chicago, Ill. Application September 2, 1938, Serial No. 228,175

13 Claims.

The present invention relates to improvements in signaling apparatus, and more in particular to improvements in traffic signaling apparatus such as is used to control vehicular traino at street intersections. The object of the invention is to provide more eicient and satisfactory signaling apparatus of this character than has been available heretofore.

A special object of the invention is to provide, in addition to the usual stop and go signals, a progressively movable signal which will at all times indicate to traffic the instant condition of the stop or go signals, as the case may be, as regards the time such signals have been on and the time remaining before a change will occur.

A further object of the invention is the provision of arrangements for a signaling apparatus of this general character whereby the duration of the stop and go periods can be regulated or controlled at will from a remote point7 preferably a central control station for controlling a plurality of such signals.

A further object of the invention is the provision of simple and eicient supervisory circuits whereby the dispatcher at the control station can readily supervise the operation of the signaling apparatus at a remote street intersection.

Other objects and features will be explained more in detail hereinafter in the course of a description of the invention with reference to the accompanying drawings, in which- Fig. 1 is a general View of the complete trafc signal as seen from the street;

Fig. 2 is a section on the line 2 2, Fig. 1, showing among other for driving the progressively movable signals;

Fig. 3 is another view of the drive mechanism, with the casing and other parts removed;

Fig. 4 is a rear view of a colored glass disc or panel which is associated with one of the pros gressively movable signals; and

Fig. 5 is a diagrammatic circuit drawing showing a complete signaling apparatus with the means for controlling and supervising it from a remote control station.

Referring to Fig. l, the reference character 2 indicates a base, which supports the casing t on a column or post 3. The base Z may be located at the center of a street intersection and is preferably of concrete or other substantial construe.. if.

tion. It has a space inside beneath the post 3 and functions also as a housing for certain parts of the apparatus. This space may be accessible through a door 5 at one side of the base, as indicated in the drawings.

details part of the mechanism The post 3 and the ber 2l at the bottom.

' motor 59, which may be casing 4 may be of any suitable construction, as shown, although the former -may' conveniently be made of a section of steel pipe.

To avoid confusionin further explanation it will be assumed that Fig. 1 shows the signaling device as seen from the south; The directions are all indicated in Fig. 2. All four sides of the casing are equipped in the same manner and consequently an explanationr of the south side which appears in the drawings will suffice.

The reference characters E and 1 indicate windows of green and red glass, respectively, behind which are positioned the lamps 9 and Il, shown in dotted lines. These are the usual red and green stop and go lights, and may be provided with the hoods l2 and I3.

Between the stop and go lights there is located a composite glass panel or window indicated generally by the reference character 8. This panel is shown in detail in Fig. 4, which is a view from the inside of the casing. As shown, the panel comprises a disc of uncolored glass IQ on the back of which is secured, by means of transparent cement, a smaller opaque disc 22, two segments I6 and l1 of yellow glass, and two segments I5 and i8 of green and red glass, respectively. The complete panel is held in position vby members l 9 and 20 at the sides and by a mem- Behind the composite panel 8 there is a lamp li), which is rotated in a clockwise direction by mechanism which will shortly be described.

As mentioned hereinbefore, thev signaling device presents the same appearance from the north, west, and east as from the south; that is, all four sides are equipped with stop and go lights and with a rotating lamp behind a composite panel. These rotating lamps function as warning signals to indicate an impending change from stop to go, and vice versa, and also function to give the yellow neutral signal.

Referring now to Figs. 2 and k3, the mechanism for rotating the lamps such as i9 will be eX- plained. The source of power is a variable speed a series wound direct current motor. This motor drives a shaft 55 by means of the worm 53 and gear 5l. Mounted on the shaft 55 is a single toothed pinion 5% which rotates the gear 54, one tooth for each complete rotation of the shaft 55. These parts are conventionally shown and are located in the base 2. It will be understood that suitable accessories such as bearings for the shafts are nrovided.

The gear 54 is mounted at the lower end of the main drive shaft 30, which extends vertically upward through the pipe 3 into the casing 4. The pipe 3 also extends within the casing for a short distance and at the top is provided with a cap member 53 which provides a bearing for shaft 30 and also supports the ring 50 by means of two brackets 5| and 52. The ring 50 affords means for mounting various parts, including the four short horizontal shafts 36, 31, 38, and 39. The shaft 3S has bearings in a U-shaped bracket 40 which is seen clearly in Figs. 2 and 3 and which is attached securely to the ring 50. Shafts 31, 38, and 39 are similarly supported in bearings in brackets 4|, 42, and 43. The gear 3| is supported on the upper end of shaft 30 and drives the shafts 36, 31, 38, and 39 through the medium of gears 32, 33, 34, and 35, respectively. The gear ratio is 2 to 1.

At the outer end of shaft 36 there. is secured an arm 44 on which is mounted a guard or holder 26 for the lamp 23. The holder is open only in front or toward the composite panel illuminated by lamp 23 and confines the illumination thereof to a section the width .of the yellow section I6 or I1. The holder also serves as a reflector. The arrangements forY lamps 24, 25, and l0 are the same as that described in the case oflamp 23. That is, these lamps are provided with holders 21, 28, and 29, which are supported on arms 45, 46, and 41, 38, and 39, respectively.

The electrical connections for lamp 23 include a brush holder 64 mounted on the ring 50 and having a brush which presses against the slip ring 69 on shaft 36. The shaft 35 is preferably hollow. The slip ring 60 may have a conductor attached to it which passes through a small hole into the'hollow shaft 36 and thence through the shaft to one terminal Yof the socket in .which lamp 23 is mounted. The other terminal of the socket maybe grounded. Lamps 24, 25, and l0 are similarly connectedthrough slip rings 6|, 62, and 63, and brush holders 65, 66, and 61.

For the purpose of lcontrolling certain circuits, the shaft 33 is provided with a cam 68 and the shaft 39 is provided with two cams 69 and 18. Each cam'operates a set of contact springswhich is suitably supported .on the ring 50. The shape of the cams and the arrangement of the different sets of contact .springs controlled thereby can be best understoodfrom Fig. 5, in connection with which these parts will be more fully explained shortly.

The direction of rotation of shaft 30 is clockwise, as seen from the top, as in Fig. 2, which means thateach ofthe lamps such as I0 rotates in a clockwise direction, as seen from in front. Being driven from the same shaft 30, through the medium of bevel gear 3|- and identical gears .t2-35, these lamps .always rotate in synchronism and at all times occupy corresponding positions in rear of their associated panel, with the exception that the west and east lamps 25 and 23 are displaced .180 from the north and south lamps 24 and VI0. The lamps do not rotate continuously, but advance step by step or intermittently, due to the arrangement including the gear 54 and the single toothed pinion 56. The number of teeth on the gear 54 bears a special relation to the subdivisions ofthe panel such as 8. Referring to Fig. 4, each yellow segment subtends an arc of 20, and the green and red segments subtend arcs of 160 each. The gear 54 has 36 teeth. It will be understood now thatvat each rotation of shaft 55, gear 54 will be roattached to shafts 31,

CII

tated the distance of one tooth, or and that since the gear ratio between gear 3| and gears such as 32 is 2 to l, the shafts such as 36 will be rotated This distance corresponds to the width of the yellow segments l5 and |1, and is one-eighth the width of the green and red segments. The lamps such as I0, therefore, have eighteen different positions, as indicated in Fig. 1, which shows the lamp I0 and indicates its positions in radial dotted lines. In two of these positions the lamp |0 is in the rear of one or the other of the yellow segments; in eight positions it is in rear of the green segment; and in the eight remaining positions it is in rear of the red segment.

Referring now to Fig. 5, the lamps 23, 24, 25,

' and l0 are indicated diagrammatically at the stood, but it may be left, with their associated slip rings and brushes. These parts bear the same reference numerals as in Fig, 2. The cam 68 on shaft 38 is shown also, together with the contact sets controlled thereby. There are two of these contact sets, one comprising the movable or working contact springs |00 and |0I, and the other comprising similar contact springs |02 and |03. The cams 69 and 10 on shaft 39 are also shown. The former controls a contact set comprising working contact springs |04 and |05, and the latter controls the working contact spring |06'. ItWill be understood that in each case the working contact springs are tensioned against their associated cams.

The drawing also shows the green go lamp 9, located on the south side of the signaling device, together with the remaining green lamps ||0, and 2, which are located on the north, west, and east sides, respectively, as indicated. The four red lamps for the stop signals are in a group below and are indicated by the reference numerals ||3, ||4, and ||5.

The reference character SI indicates a stepby-step switch comprising the stepping magnet |23, the wiper |20, and a bank of five contacts, as indicated. This switch may be of the well known type in common use in automatic telephone systems, and for other purposes, and is more fully disclosed in U. S. patent to Erickson, No. 1,794,888, granted March 3, 1931'. 'I'he operation of a switch of this type is well understated that the wiper is advanced on the deenergization of the associated stepping magnet rather than upon the energization thereof, and that the wiper has a forward movement only. In the case of switch SI, for instance, the wiper |20 is shown in engagement with the fourth contact in its bank. On energization and deenergization of the magnet |23, the wiper will be advanced one step into engagement with the fifth contact, and one additional step will bring the other end of the wiper into engagement with the first contact.

Switches S2, S3, and S4 are similar to switch SI. The two former are exactly `the same as switch SI, and switch S4 is of similar construction, but has two wipers |49 and |4|, and each wiper has six contacts inV its bank.

The reference character B indicates a battery for supplying operating current. Suitable automatic charging equipment may be provided to keep the battery charged, but as this is of well known'construction and has nothing to do with the invention, it is now shown herein. The relays |28 and |21 are provided for starting and stopping the operation of the signaling device by connecting and disconnecting the battery B, 'as will be explained shortly.

Relays |42, |43, and |44 are control relays which are associated with the line comprising conductors |50 and |5| extending to the control station. Conductor |50 is used for operating the switches S4, Sl, S2, and S3, while conductor is used for supervision.

The parts just described, including the switches, relays, and the battery B, may be located in the base, suitable mounting provisions of known character being provided. The wiring may also be of any approved character, and will necessarily include a cable extending through the post 3 to connect the parts in the base with those in the casing 4.

The equipment at the control station comprises the switching key Kl, the voltage control key K2, the battery B2, the key or push button P, the supervisory lamp L, and the milliammeter M. The latter has associated with it a variable resistance for adjustment purposes. All of this equipment except the key Kl and lamp L may be common to other control lines such as the line comprising conductors |50 and |5|.

The operation of the complete signaling device and the controlling equipment will now be explained, reference being had especially to Fig. 5. It will be assumed that all the parts are in the position in which they are shown. It will be understood, therefore, that the signaling device is not operating, as relay |28 is deenergized and the battery B is disconnected from conductor |60, over which current is supplied to the motor 59 and to the vvarious lamps of the signaling device.

In order to place the signaling device in operation, the dispatcher will first actuate the key Kl to associate the common equipment at the control station with the control line |50|5|. Upon the actuation of the key, a circuit is completed from battery B by way of the resistance |35, wiper |4| of switch S4, c-ontact |41 of relay |44, line conductor 15|, key KI, the milliammeter M, and the Variable resistance |48 to ground. The value of the resistance |35 may be such that with the battery B in its average state of charge a current of 40 milliamperes will flow over the above circuit. The milliammeter may have a range of 0 to 100 milliarnperes. These values are, of course, given merely by way of example. Noting the reading of the milliammeter M, the dispatcher is informed thereby that switch S4 is in position as only in this position are the circuit conditions such that a reading in the vicinity of 40 can be obtained. If the reading is not exactly 40, the dispatcher may make the necessary adjustment of the variable resistance |48, so that subsequent readings will be exactly in accordance with the values selected to convey the diierent items of information which the dispatcher obtains over the supervisory circuit.

The dispatcher now operates the push button P ve times in order to advance the switch S4 ve steps into position 6, which is the starting position. Each time the push button is actuated a circuit is completed by way of a section of battery B2, key K2, push button P, key Kl, line conductor |50, and relays |42 and |43 to ground. Relay |42 is marginally adjusted and does not operate over the above circuit. Relay |43 operates each time the circuit is closed, and accordingly transmits five impulses to the stepping magnet |25 o f switch S4. On each impulse the magnet energizes and deenergizes, which advances the wipers |40 and |4| one step, with the result that after ve impulses have been transmitted the wipers will have been advanced to position 0. While transmitting impulses to magnet |26, the relay |43 also transmits impulses to the slow-releasing relay |44, which energizes and due to its slow-releasing characteristic stays in operated position throughout the series of impulses, holding open the supervisory circuit at contact |41. At the end of the series of impulses relay |44 deenergizes and closes the supervisory circuit.

In position 5 of switch S4 the supervisory circuit includes the resistance |32, the value of which may be such that the milliammeter M will show a reading of l0. Being thus advised that the switch is in the desired position, the dispatcher will actuate the key K2 and will then operate the push button P again to send another impulse over line conductor |50. With key K2 actuated, the circuit includes the entire battery B2 and both relays |42 and |43 are energized, with the result that a circuit is closed in an obvious manner through contacts |46 and |45 and wiper |40 in position 6 to the relay |28. On reenergizing, relay |28 locks itself at contact |30 and connects the battery B to conductor |50 at contact |29.

The supervisory circuit is momentarily opened by relay |44 during the foregoing operation, of course, but is again closed ,after relay 628 has energized. It should be noted at this point that the dispatcher is advised of the proper energization of relay |28 by the slight decrease in the reading of the milliammeter, due to the slight fall in potential at battery B when current consumption. due to operation of the signaling device, begins. The change in the reading will be very small, but is suii'icient to be detected. If desired, a very low resistance |34 may be inserted in series with the battery, but ordinarily will not be required. Contacts on relay |28 could be employed to vary the value of resistance |32, but such arrangement would merely indicate the energization of relay |28, and the arrangement shown is therefore to be preferred as it depends on actual current drain from battery B, whichcan only take place by the operation of the signaling device.

When the battery B is connected to conductor |00 as previously described, circuits are completed for lighting the lamps 23, 24, 25, and I0, and also a circuit is completed for the motor 59, the latter circuit extending through the mo tor and by way of resistance |51, wiper |22 of switch S3, conductor |35, and contact spring to ground. The lamps mentioned light up, and the motor 59 starts. As will be noted, this cycle of the operation requires that Contact |05 is closed as shown in the drawings, connecting ground to conductor |65 and wiper |22 of switch S3. In other words, the cam 69 must have come to rest at the end of a previous operation, when the system was switched off, in the position in which it is shown. It may happen, however, that the system is switched oi when this cam is in an off-position, keeping the contact |05 open. In this case, cam 08 would also be at a corresponding angular off-position andwould keep closed either the contacts E00 or |02. In the first case, ground would be supplied for'the operation of the motor 53 over wiper |20 of switch Si, or, in the second case, over conductor |53 and wiper |2| y of switch S2. Motor 59 therefore starts operating in any case. The speed of the motor is de-` termined by the value of the resistance .over

which .its starting circuit sumed .case by the value four of the lamps 23, 24, 25, and l| 9 are in horizontal positions in rear of yellow segments in their associated panels, and consequently the signaling device displays a yellow or caution signal in all directions.

As the motor continues to drive shaft 55, the single Vtooth on pinion 55 will eventually engage gear 54 and will rotate said gear the distance of one tooth, or 10, as previously explained. The four shafts 36-39 are accordingly rotated and the four lamps 23, 24, 2'5, and I0 are advanced the same distance to their next positions. In the case of lamp I0, the next position is in rear of the green segment and the same is true of lamp y24 on the north side of the signaling device. Lamps 25 and 23 on the west and east sides, respectively, are displaced 180 from is closed, in the first asof resistance |51. All

lamps 24 and l0, and accordingly move to positions in rear of the corresponding red segments.

When the shafts 38 and 39 are rotated as described, the cams 58, 69, and 'NJ are also rotated, with the result that conductors |51 and |52 are grounded by springs |00 and HH cam 68, while ground is removed from conductor |65 at contact spring |05 associated with cam 69. The grounding of conductor |62 establishes a new circuit for motor 59, said circuit including the Wiper |20 of switch S| and resistance |55. The grounding of conductor |6| completes circuits in an obvious manner for the green lamps ||9 and 9 on the north and south sides of the signaling device. The lamps accordingly display a go signal for north and south traffic. The grounding of conductor IGI also completes circuits for the red lamps ||4 and ||5 on the west and east sides of the signaling device, and these lamps accordingly display stop signals.

As the motor A:59 continues to run, at a speed determined by the value of resistance |55, the lamps 24 and I9 are intermittently advanced to successive positions behind the green segments in their associated panels, and lamps 25 and 2:3

are similarly advanced to successive positions behind the red segments in their associated panels. These lamps accordingly show by their positions the approximate length of time that the go and stop signals have been on, and as they reach their last positions next to the yellow segments they give warning of the impending change.

When the shafts 38 and 39 have rotated 180 from the position shown in the drawings, conductor |55 will again be grounded by cam 69, and ground will be removed from conductors |6| and 62 by cam 69. The motor 59 now runs for an interval at a speed determined by resistance |51, and the lamps H0, 9, H4, and ||5 are extinguished. Lamps 23, 2'4, V25, and I9 display caution signals.

On the next rotation of shafts 38 and 39, cam 68 operates springs |92 and |03 to ground conductors |53 and |54, and cam 69 removes ground from conductor |55. By the grounding of conductor |63 a new circuit is completed for motor 59, the circuit including the wiper |21 of switch S2 and resistance |55. By the grounding of conductor |64, circuits are completed for red lamps H3 and and for green lamps and ||2. Stop signals are thus displayed to north and south trafc and go signals to west and east traic. The rotation of shafts -39 has also advanced the lamps 24 and i9 into their rst positions in rear of the red segments of their associated with associated panels, while lamps '25 and 123 have been advanced to their rst positions in rear of the green segments of their associated panels.

'I'he apparatus continues to operate in the manner described, alternating the north and south trailic with the west and east tra-inc in a manner which will be clearly understood. Three different circuits are employed for the motor 59, as explained, whereby the duration of the signals north and south and east and west can be adjusted in accordance with trail-lc requirements.

The manner in which this is done will present'- ly be explained, after rst considering the supervisory circuits over which the dispatcher is advised as to the rate at which the signals are changing at any given time and the relative duration of the stop and go periods in any given direction.

Having started the apparatus in operation as described, if the dispatcher desires to check up on the signal changes, he will restore key K2 and transmit two impulses over the line by means of the push button P. In response to these impulses relay |43 energizes twice and transmits two impulses to magnet |26, stepping the switch S4 from position 6 to position 2. In this position of the switch the supervisory circuit extends from battery B by way of conductor 50, conductor |67, resistance ||8 (either alone or in parallel with resistance H3 or resistance Ill), Wiper |4| in position 2, contact |41, conductor |5|, switch KI, milliammeter M, and resistance |48 to ground. The resistances H6, IIT, and I8 may have such values that with resistance ||8 alone in the circuit a reading of S5 will be obtained, resistances ||8 and H5 in parallel will give a with the opera-tion of the signaling device, it will nals displayed. In this position, and also in a position 180 farther on, cam 69 connects resistance IIS in parallel with resistance ||8 at contact |94, giving a reading of on the milliammeter M. This reading, therefore, indicates to the dispatcher that the yellow signals are being displayed.

As the apparatus continues to operate, cam 69 will disconnect resistance ||6 and cam 'l0 will connect up resistance The latter resistance in parallel with resistance ||8 gives a reading of 95, which is obtained during the go period for north and south traflic, which corremeter will therefore again read 80, indicating the cams advance again, resistance ||6 is disconnected, and as resistance is not connected being displayed for north and south trac and the go signals are being displayed for west and east traffic.

Thus the dispatcher, by observing the milliammeter, is able to tell at all times what conditions at the signaling device and can time the duration of any particular signal at will.

v should change at a As the apparatus is shown in the drawings, the north and south go signals will be lighted for much longer periods than the corresponding stop signals; that is, the apparatus is set to handle a much greater volume of traffic north and south than east and west. If trafc conditions particular time of the day, the dispatcher can alter the stop and go periods accordingly by resetting switches SI and S2. The manner in which this is done will now be explained.

With key K2 in normal position, the dispatcher first transmits sufficient impulses by means of push button P to restore switch S4 to position These impulses may be spaced sufficiently to allow relay |44 to deenergize after each impulse, and the dispatcher will accordingly be advised of the arrival of switch S4 in position by the milliammeter showing a reading of 40, as previously mentioned. Two more impulses are now transmitted, advancing switch S4 to position 3, in which wiper |40 is associated with the stepping magnet |24 of switch S2. Key K2 is now operated, and the push button P is again operated one or more times, depending on the amount of change that is to be eiected. If the relative duration of the stop and go periods is to be exactly reversed, the push button will be operated three times, to transmit three impulses over the line. Relays |42 and |43 respond to these impulses and transmit three impulses to stepping magnet |24 of switch S2, which is accordingly advanced to position 4.

The dispatcher now restores key K2 and operates the push button P to transmit a single impulse over the line, which energizes relay |43 to transmit an impulse to stepping magnet |26 of switch S4. This switch is therefore advanced to position 4, in which wiper |40 is associated with the stepping magnet |23 of switch SI. The key K2 is now again operated, followed by the operation of the push button P a suicient number of times to advance switch SI from position 4 to position I, or two impulses. The dispatcher knowshow many impulses to transmit to properly reset switches S2 and Sl, either by maintaining a record of the position of the switches, or by timing the stop and go periods prior to the resetting operation to ascertain the instant setting.

The eiect of the changed setting of switches SI and S2 may now be explained briefly. During the period in which the green lamps north and south are lighted to display go signals in these directions, the conductor |62 is grounded and the speed of the motor is governed by the resistance with which wiper of switch Sl is associated. This wiper is now in position instead of position 4 as formerly, and the resistance |10 is in circuit insteadv of resistance |55. As resistance |10 is of lower value than resistance |55, the motor 59 will now run faster than before, and the go periods for north and south trafc will be correspondingly shortened. The stop periods for west and east traiiic, which coincides with the go periods for north and south trafiic, will be shortened at the same time. When the stop signals north and south are displayed, the conductor |63 is grounded and the speed of the motor 59 is determined by the value of the resistance with which wiper |2| of switch S2 is associated. This switch has been advanced to position 4, connecting resistance |1| in circuit in place of resistance |56. As the former resistance is greater than the latter, the motor 59 runs slower and the duration of the stop periods for north and south traii'ic is increased. At the same time the go periods for west and east trame are also increased.

It will be apparent that the dispatcher can also regulate the duration of the yellow caution signals by changing the setting of switch S3. This is accomplished by first setting switch S4 in position 2, and by then transmitting the proper number of impulses to reset switch S3 to the desired position, as will be readily understood.

In any position of switch S4 in which it is associated with one of the switches SI, S2, or S3, the supervisory circuit including wiper |4| will be closed so that immediately after any resetting operation has been completed, the dispatcher can check the result by observation of the milliammeter.

During the early morning hours, say from 1:00v a. m. to 5:00 a. m., it may be desirable to stop the operation of the .traiilc signaling device to avoid delay to the occasional vehicles which may pass during this period. In order to shut down the signaling device, the dispatcher on duty will step switch S4 to position 5 in the manner previously explained and will then, after rst actuating key K2, depress the push button P to close a circuit for relay |21. Relays |42 and |43 respond to the actuation of the push button and the circuit or relay |21 is closed over contacts |46 and |45 of these relays and wiper |40 in position 5. On energizing, relay |21 breaks` the locking circuit of relay |28, which deenergizes and disconnects the battery B from conductor |60 over which current is supplied to the motor 59, and the various lamps of the signaling device. At the time of shutting down the system, the switches SI, S2, S3 may be in any assumed position, and the control cams 68, 69, 10 may likewise stop either in the positions in which they are shown or in any-other position. As previously explained, the system is ready for reoperation regardless oi the position of the switches orA cams, because ground will be supplied to the motor 59 over one of the conductors |62, |63

, or |65, and will complete the motor circuit as soon as battery is again connected to the conductor |60.

The supervisory circuit enables the dispatcher to check the position of switch S4 after it has been set to position 5 (presumably), as in position 5 the resistance |33 is included in the circuit. This resistance has the proper value to give a reading of 20 on the milliammeter M, and if such reading is observed it indicates that switch S4 is in the desired position. By checking the position of the switch in this manner before actuating the push button P, the dispatcher is able to avoid any chance of disturbing switches Sl, S2, or S3, due to accidental positioning of switch S4 in position 2, 3, or 4 instead of in position 5. The supervisory circuit also serves to notify the dispatcher that the battery B has actually been disconnected after the shutdown procedure is completed. When the relay deenergizes and opens contact |29 to disconnect the battery B, it breaks the supervisory circuit at this point and the milliammeter reading will drop to zero.

It has been mentioned already that the control equipment shown is common to the line |50|5| and other similar lines. When the control equipment is not in use on line |50-|5|, it is disconnected therefrom by restoration of key Kl. With the key in normal position, conductor |5l is connected to the supervisory lamp L,

- ine. eqliel and disposed V180,"

which will light up fully only when the supervisory circuit includes resistances H8 and H7 in parallel, which is the condition in which the supervisory circuit has the least resistance. With resistance llt in the circuit alone, or with resistance H6 in parallel with resistance l l, the lamp L will be correspondingly dimmed. It will be clear therefore that if the dispatcher leaves the switch S4 in position 2, 3, or ll at the time the key Kl is restored the lamp L will give a continuous supervision of the opera-tion of the signaling device shown. Other signaling devices are of course similarly provided with lamps such as L, so that the dispatcher can watch the operar system, using the common equipment only when it is necessary to start or stop some signaling device, or reset one or Amore oi tlie switches The invention `.having been desoribed., what is Considered to be new and ,for which the preteetion Aolf Letters Patent is desired, will be pointed ont. in the, appended eleilns- I Iclairn;

1..V In a trame signaling device, a roundv transparent panel. having refiero green seotions seperated by yellow sections, the yellow sections beapart, the red and green sections also being equal and having an angular width which is an exact multiple of the yellow sections, a light behind Vsaid panel, a shaft for rotating said light, and means for intermittently rotating said shaft in steps, the anguiar distance moved in each step being exactly equal to the angular width orf4 said yellow sections..

v2,. In a traffic signaling device, red and green lights indicating stop` and go, respectively, a third light, means for alternately illuminating said red and green lights, means operating in timed relation with the alternate illumination of said red and green lightsA for rotating said third lient step-bv-step through e plurality of iiXed positionsI sind filtering Ineens effettive in each said position for causing said third light to give e red. or eieensienei eeoordiristo Whether the said red or green light is illuminated at the time.

3. Inra traiicsignaling device, redandgreen lights imitating. stop ,and go, respectively, a third light, a rotatable shaft onwhich said thirdlight is inoiinted, ineens for intermittently rotating saidshaft to cause saidthird light toA assume siiooessive stationery positions in e, Circuler path, switching means, cammeans on said shaft for operating said switching means during non-successive movements of the shaft, and circuits controlied by said` switching means for alternately illuminating saidred and green lights.

4. In a tralic signaling device, red andgieen lightsindicating stop and go, respectively, a third light, means for alternately illuminating the said red and green lights, means for intermittently rotating said third light in timed relation therewith, means including a redv andv green filter panel in front of said third light to associate the saine with either the stop light or the go light, depending on which one is illuminated, and shielding means associated with said third light for conning the illumination of said panel t0. allY area which` is equal to the total area of the panel divided by the number of movements of said third light requiredV fora complete rotation thereof.

5. In a traino signal, a source of light, means for rotating said light in a seriesof steps, in

aeeaaoee oludiiigmeans for holding between successive steps, means for causing said source to display a particular traic controlisignal in one of its stationary positions, andmeans for Vcausing vsaid source to display a diilerent traflic control signal in another stationary p osition.

6. In a traffic signal, a source of light, means for rotating said light in a series of steps, including means for holding said source stationary between successive steps, means for causingsaid source to display a particular traffic control signal in one ofits stationary positions, and means for causing said source to display two additional traffic control signals in two other stationary positions, respectively.

7. In a traffic signal, ,a source of light, means for supporting said source in a plurality of different stationary positions, intermittently Voperatedmeans for moving said ,source to its, different positions4 successively, source to display a lcaution signal While remaining stationary in one position, and meansA for causing said source to source tor display a caution signal in one of.its. means` for causing said` source to display a stop signalV in another. of its. and meansfor causing said.

stationary positions,

stationary positions, source to display a go` signal in another of` its stationary positions..

9. In a trame signal, a source ofilight., meansl for rotating4 said source in a, series of steps in meansfor holding said lsource stationary between successive steps, two filtering mediums.

to the filter Inediumin the other position.

10, In a vtrame signal, a source of light, meansA for rotatingsaid source inaseries of steps, inc ludingimeans for holding said source stationary between successivesteps, means for conning the light transmittedV light ltering mediums on which said beam'impinges, the area of each'saidmediumbeing equal to or anexact multiple of thecross-sectional area.

determined unit area, alight source behind said:

paneLvrneans for causing said; nate` only one said unit Varea at for moving said4 sourcev atV sourcek to illumispaced intervals through a predetermined distance equalto the.

distance between thev centers areas, whereby saidV unitv areas aren illuminated.

successively.

12. In a trac signal, adisplay panel comprising two different to Signalj stop and.

colored filter sectionsA adapted light source behind said panel, means for re- Said source stationalii means for causing said.

ofv light, andmeans effective is ineither of said positions, for preventing said source Vfrom transmitting lightY from said source to a beamofi limited cross-sectional area, and a plurality of,

. Y poSition-thatin. each stationary position ofsaid. source the said:

a time, and means,

go, respectively, and an inten, vening filter section adaptedto signal cautionL a,

stricting the light reaching said panel from said source to an area equal to the area of said caution section, and means for moving said source in steps separated by stationary periods in one of which said source illuminates only the said lter section which signals caution, whereas in the next preceding and following periods the said source illuminates only the stop and go ilter sections, respectively.

13. In a traic signal, a light source, means supporting said source for rotation in a circular path, means for giving said source an intermittent motion along said path, whereby said source is caused to occupy successive stationary positions, a display panel in front of said source, means for causing said source to illuminate different distinct areas of said panel in the successivevpositions occupied by said source, respectively, and different colored filter sections composing said panel, each section having an area equal to or an exact multiple of the area illuminated by the said source, the said sections being so arranged relative to the stationary positions of said source that parts of two adjacent sections are not illuminated in any stationary position.

. JOHANNES GANDL. 

